Blocks not playing well together with Brick components

[pablobm]

I just came across a problem when I was mixing together Building Blocks (specifically headers) and components from Mozilla's Brick http://mozilla.github.io/brick/ (specifically x-layout).

Turns out these two don't work that well together because the CSS selectors for Building Blocks are too specific. For example, I was able to fix some things by replacing every instance of section[role=region] with [role=region].

My question: do blocks need to have so specific selectors? Could these be relaxed a bit so that they can play better with other libraries?

I guess a longer-term question would be: do Mozilla/FirefoxOS have plans to turn Building Blocks into x-tag elements?